An adolescent case of ASXL3-related disorder with delayed onset of feeding difficulty.

BACKGROUND: ASXL3-related disorder, first described in 2013, is a genetic disorder with an autosomal dominant inheritance that is caused by a heterozygous loss-of-function variant in ASXL3. The most characteristic feature is neurodevelopmental delay with consistently limited speech. Feeding difficulty is a main symptom observed in infancy. However, no adolescent case has been reported. CASE PRESENTATION: A 14-year-old girl with ASXL3-related syndrome was referred to our hospital with subacute onset of emotional lability. Limbic encephalitis was ruled out by examination; however, the patient gradually showed a lack of interest in eating, with decreased diet volume. Consequently, she experienced significant weight loss. She experienced no symptoms of bulimia, or food allergy; therefore, avoidant/restrictive food intake disorder (ARFID) was clinically suspected. CONCLUSIONS: We reported the first case of ASXL3-related disorder with adolescent onset of feeding difficulty. ARFID was considered a cause of the feeding difficulty.

Efficient detection of copy-number variations using exome data: Batch- and sex-based analyses.

Many algorithms to detect copy number variations (CNVs) using exome sequencing (ES) data have been reported and evaluated on their sensitivity and specificity, reproducibility, and precision. However, operational optimization of such algorithms for a better performance has not been fully addressed. ES of 1199 samples including 763 patients with different disease profiles was performed. ES data were analyzed to detect CNVs by both the eXome Hidden Markov Model (XHMM) and modified Nord's method. To efficiently detect rare CNVs, we aimed to decrease sequencing biases by analyzing, at the same time, the data of all unrelated samples sequenced in the same flow cell as a batch, and to eliminate sex effects of X-linked CNVs by analyzing female and male sequences separately. We also applied several filtering steps for more efficient CNV selection. The average number of CNVs detected in one sample was <5. This optimization together with targeted CNV analysis by Nord's method identified pathogenic/likely pathogenic CNVs in 34 patients (4.5%, 34/763). In particular, among 142 patients with epilepsy, the current protocol detected clinically relevant CNVs in 19 (13.4%) patients, whereas the previous protocol identified them in only 14 (9.9%) patients. Thus, this batch-based XHMM analysis efficiently selected rare pathogenic CNVs in genetic diseases.

MACF1 Mutations Encoding Highly Conserved Zinc-Binding Residues of the GAR Domain Cause Defects in Neuronal Migration and Axon Guidance.

To date, mutations in 15 actin- or microtubule-associated genes have been associated with the cortical malformation lissencephaly and variable brainstem hypoplasia. During a multicenter review, we recognized a rare lissencephaly variant with a complex brainstem malformation in three unrelated children. We searched our large brain-malformation databases and found another five children with this malformation (as well as one with a less severe variant), analyzed available whole-exome or -genome sequencing data, and tested ciliogenesis in two affected individuals. The brain malformation comprised posterior predominant lissencephaly and midline crossing defects consisting of absent anterior commissure and a striking W-shaped brainstem malformation caused by small or absent pontine crossing fibers. We discovered heterozygous de novo missense variants or an in-frame deletion involving highly conserved zinc-binding residues within the GAR domain of MACF1 in the first eight subjects. We studied cilium formation and found a higher proportion of mutant cells with short cilia than of control cells with short cilia. A ninth child had similar lissencephaly but only subtle brainstem dysplasia associated with a heterozygous de novo missense variant in the spectrin repeat domain of MACF1. Thus, we report variants of the microtubule-binding GAR domain of MACF1 as the cause of a distinctive and most likely pathognomonic brain malformation. A gain-of-function or dominant-negative mechanism appears likely given that many heterozygous mutations leading to protein truncation are included in the ExAC Browser. However, three de novo variants in MACF1 have been observed in large schizophrenia cohorts.

Biallelic KARS pathogenic variants cause an early-onset progressive leukodystrophy.

The leukodystrophies cause severe neurodevelopmental defects from birth and follow an incurable and progressive course that often leads to premature death. It has recently been reported that abnormalities in aminoacyl t-RNA synthetase (ARS) genes are linked to various unique leukodystrophies and leukoencephalopathies. Aminoacyl t-RNA synthetase proteins are fundamentally known as the first enzymes of translation, catalysing the conjugation of amino acids to cognate tRNAs for protein synthesis. It is known that certain aminoacyl t-RNA synthetase have multiple non-canonical roles in both transcription and translation, and their disruption results in varied and complicated phenotypes. We clinically and genetically studied seven patients (six male and one female; aged 2 to 12 years) from five unrelated families who all showed the same phenotypes of severe developmental delay or arrest (7/7), hypotonia (6/7), deafness (7/7) and inability to speak (6/7). The subjects further developed intractable epilepsy (7/7) and nystagmus (6/6) with increasing age. They demonstrated characteristic laboratory data, including increased lactate and/or pyruvate levels (7/7), and imaging findings (7/7), including calcification and abnormal signals in the white matter and pathological involvement (2/2) of the corticospinal tracts. Through whole-exome sequencing, we discovered genetic abnormalities in lysyl-tRNA synthetase (KARS). All patients harboured the variant [c.1786C>T, p.Leu596Phe] KARS isoform 1 ([c.1702C>T, p.Leu568Phe] of KARS isoform 2) either in the homozygous state or compound heterozygous state with the following KARS variants, [c.879+1G>A; c.1786C>T, p.Glu252_Glu293del; p.Leu596Phe] ([c.795+1G>A; c.1702C>T, p.Glu224_Glu255del; p.Leu568Phe]) and [c.650G>A; c.1786C>T, p.Gly217Asp; p.Leu596Phe] ([c.566G>A; c.1702C>T, p.Gly189Asp; p.Leu568Phe]). Moreover, similarly disrupted lysyl-tRNA synthetase (LysRS) proteins showed reduced enzymatic activities and abnormal CNSs in Xenopus embryos. Additionally, LysRS acts as a non-canonical inducer of the immune response and has transcriptional activity. We speculated that the complex functions of the abnormal LysRS proteins led to the severe phenotypes in our patients. These KARS pathological variants are novel, including the variant [c.1786C>T; p.Leu596Phe] (c.1702C>T; p.Leu568Phe) shared by all patients in the homozygous or compound-heterozygous state. This common position may play an important role in the development of severe progressive leukodystrophy. Further research is warranted to further elucidate this relationship and to investigate how specific mutated LysRS proteins function to understand the broad spectrum of KARS-related diseases.

Genetic landscape of Rett syndrome-like phenotypes revealed by whole exome sequencing.

BACKGROUND: Rett syndrome (RTT) is a characteristic neurological disease presenting with regressive loss of neurodevelopmental milestones. Typical RTT is generally caused by abnormality of methyl-CpG binding protein 2 (MECP2). Our objective to investigate the genetic landscape of MECP2-negative typical/atypical RTT and RTT-like phenotypes using whole exome sequencing (WES). METHODS: We performed WES on 77 MECP2-negative patients either with typical RTT (n=11), atypical RTT (n=22) or RTT-like phenotypes (n=44) incompatible with the RTT criteria. RESULTS: Pathogenic or likely pathogenic single-nucleotide variants in 28 known genes were found in 39 of 77 (50.6%) patients. WES-based CNV analysis revealed pathogenic deletions involving six known genes (including MECP2) in 8 of 77 (10.4%) patients. Overall, diagnostic yield was 47 of 77 (61.0 %). Furthermore, strong candidate variants were found in four novel genes: a de novo variant in each of ATPase H+ transporting V0 subunit A1 (ATP6V0A1), ubiquitin-specific peptidase 8 (USP8) and microtubule-associated serine/threonine kinase 3 (MAST3), as well as biallelic variants in nuclear receptor corepressor 2 (NCOR2). CONCLUSIONS: Our study provides a new landscape including additional genetic variants contributing to RTT-like phenotypes, highlighting the importance of comprehensive genetic analysis.

Development of a simple driving simulator and determination of the reference range of normative performance.

OBJECTIVE: To establish the reference range for assessment items of the 'Simple Driving Simulator' (SiDS) in a normative population and to compare performance of age-matched young adults with a traumatic brain injury (TBI) to this reference data. METHODS AND PROCEDURES: Normative ranges were calculated from the data of 445 participants in the control group. Three performance ranges were established: 'normal', 'borderline' and 'impaired' defined using standard deviation cutoff values in the control group. The performance of 28 patients with a TBI, aged 18-35 years, was evaluated. The performance score for the TBI group in the 'impaired range' was calculated for each test item and used to make a synthetic judgment regarding the clinical value of the SiDS. MAIN OUTCOMES AND RESULTS: In the control group, only 0.6% of the participants exhibited a performance in the impaired range on >2 items, compared to 33.2% for the TBI group. CONCLUSIONS: We provide evidence that impaired performance on ≤2 items of the SiDS provides a sensitive criterion of 'driving fitness' in young adults after a TBI.

Probing the Inhibitor versus Chaperone Properties of sp²-Iminosugars towards Human ß-Glucocerebrosidase: A Picomolar Chaperone for Gaucher Disease.

A series of sp²-iminosugar glycomimetics differing in the reducing or nonreducing character, the configurational pattern (d-gluco or l-ido), the architecture of the glycone skeleton, and the nature of the nonglycone substituent has been synthesized and assayed for their inhibition properties towards commercial glycosidases. On the basis of their affinity and selectivity towards GH1 ß-glucosidases, reducing and nonreducing bicyclic derivatives having a hydroxylation profile of structural complementarity with d-glucose and incorporating an N'-octyl-isourea or -isothiourea segment were selected for further evaluation of their inhibitory/chaperoning potential against human glucocerebrosidase (GCase). The 1-deoxynojirimycin (DNJ)-related nonreducing conjugates behaved as stronger GCase inhibitors than the reducing counterparts and exhibited potent chaperoning capabilities in Gaucher fibroblasts hosting the neuronopathic G188S/G183W mutation, the isothiourea derivative being indeed one of the most efficient chaperone candidates reported up to date (70% activity enhancement at 20 pM). At their optimal concentration, the four selected compounds promoted mutant GCase activity enhancements over 3-fold; yet, the inhibitor/chaperoning balance became unfavorable at much lower concentration for nonreducing as compared to reducing derivatives.

Effects of low-dose milnacipran on event-related potentials and neuropsychological tests in persons with traumatic brain injury: A preliminary study.

INTRODUCTION: Psychostimulants are among the most commonly used pharmacological agents for countering cognitive dysfunction and/or enhancing rehabilitation in persons with brain injury. It was postulated that milnacipran, a serotonin-norepinephrine reuptake inhibitor, would be effective against cognitive dysfunction in non-depressed persons with brain injury. METHODS: Eighteen patients were recruited with at least moderate disability more than 4 months after a traumatic brain injury (TBI) and they were randomized to an 8-week, placebo-controlled, double-blind trial. Cognitive dysfunction was assessed at baseline with the Trail Making Test, the Wechsler Adult Intelligence Scale-Revised (WAIS-R), the Wechsler Memory Scale-Revised (WMS-R) and measurement of event-related potentials (ERPs) both before randomization and after an 8-week administration of milnacipran or placebo. RESULTS: N2 and P3 latencies in the milnacipran group were significantly shortened by the intervention. Moreover, the Verbal Intelligence Quotient and Full Intelligence Quotient scores of the WAIS-R and the delayed recall score of the WMS-R were significantly higher than baseline after milnacipran intervention. CONCLUSION: Milnacipran administration improved ERP measures of attention and information processing in non-depressed persons with brain injury and also improved scores on three sub-scales of standard neuropsychological tests of cognitive dysfunction. Therefore, this intervention merits validation by additional, larger studies.

Did the educational campaign to support persons with cognitive dysfunction encourage them to participate in society in Northern Kyushu, Japan?

PRIMARY OBJECTIVE: To investigate social participation and the administration of the official certificate for cognitive dysfunction in Northern Kyushu, Japan following a government-conducted educational campaign to support persons with cognitive dysfunction. METHODS AND PROCEDURES: A questionnaire was mailed to members of the Brain Injury Association of Northern Kyushu living with traumatic brain injury; the results were compared with those of the first survey conducted in 2002. MAIN OUTCOMES AND RESULTS: This study evaluated 159 individuals (response rate: 72.6%, 135 males and 24 females), whose mean age at time of injury was 28 years. Eighty-two per cent of the participants were living at home; 72% were independent in activities of daily living. Fifty-nine per cent and 33% had certificates of physical and mental disability, respectively, and 37% were engaged in employment or school attendance. The number of participants who had obtained certificates of physical or mental disability and the number of participants who returned to employment or school significantly increased in comparison to the first survey (χ2 test, p < 0.05). CONCLUSIONS: The model project and educational campaign facilitated social participation and increased the acquisition of the official certificate of cognitive dysfunction.

First detailed case report of a pediatric patient with neuronal intranuclear inclusion disease diagnosed by NOTCH2NLC genetic testing.

INTRODUCTION: Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disease characterized clinically by eosinophilic hyaline intranuclear inclusions in neuronal and other somatic cells. Skin biopsies are reportedly useful in diagnosing NIID, and the genetic cause of NIID was identified as a GGC repeat expansion in NOTCH2NLC in recent years. The number of adult patients diagnosed via genetic testing has increased; however, there have been no detailed reports of pediatric NIID cases with GGC expansions in NOTCH2NLC. This is the first detailed report of a pediatric patient showing various neurological symptoms from the age of 10 and was ultimately diagnosed with NIID via skin biopsy and triplet repeat primed polymerase chain reaction analyses. CASE REPORT: This was an 18-year-old female who developed cyclic vomiting, distal dominant muscle weakness, and sustained miosis at 10 years. Nerve conduction studies revealed axonal degeneration, and her neuropathy had slowly progressed despite several rounds of high-dose methylprednisolone and intravenous immunoglobulin therapy. At 13 years, she had an acute encephalopathy-like episode. At 15 years, brain MRI revealed slightly high-intensity lesions on diffusion-weighted and T2-weighted imaging in the subcortical white matter of her frontal lobes that expanded over time. At 16 years, esophagography, upper gastrointestinal endoscopy, and esophageal manometry revealed esophageal achalasia, and per-oral endoscopic myotomy was performed. At 18 years, we diagnosed her with NIID based on the findings of skin specimen analyses and a GGC repeat expansion in NOTCH2NLC. CONCLUSION: NIID should be considered as a differential diagnosis in pediatric patients with various neurological symptoms.

Mastocytosis in a Case of Noonan Syndrome Caused by a De Novo Pathogenic CBL Variant.

Noonan syndrome is an autosomal dominant disease characterized by multi-organ disorders caused by variants of genes involved in the RAS/MAPK signaling pathway. The nine causative genes including PTPN11 and CBL have been identified. Mastocytosis is a disease characterized by mast cell proliferation in skin, bone marrow, and other organs. To date, no previous cases of Noonan syndrome with mastocytosis caused by a pathogenic CBL variant have been reported. A boy was diagnosed with Noonan syndrome at 8 months of age with facial features and minor anomaly of his body. He presented with brown nodules of 5-10 mm on his body since the age of 2 months. The patient was diagnosed with mastocytosis by a biopsy specimen from brown nodules, which showed infiltration of mast cells. Whole-exome sequencing of the parent-patient trio revealed a de novo pathogenic CBL variant. The occurrence of mastocytosis may be a cue for the analysis of the CBL gene in Noonan syndrome. The CBL gene is involved in mastocytosis and various cancers. In the case of the pathogenic variant, long-term follow-up for the risk of cancers related to the CBL variant is necessary.

Phase Lag Analysis Scalp Electroencephalography May Predict Seizure Frequencies in Patients with Childhood Epilepsy with Centrotemporal Spikes.

Background: Childhood epilepsy with centrotemporal spikes (CECTS) is the most common epilepsy syndrome in school-aged children. However, predictors for seizure frequency are yet to be clarified using the phase lag index (PLI) analyses. We investigated PLI of scalp electroencephalography data at onset to identify potential predictive markers for seizure times. Methods: We compared the PLIs of 13 patients with CECTS and 13 age- and sex-matched healthy controls. For the PLI analysis, we used resting-state electroencephalography data (excluding paroxysmal discharges), and analyzed the mean PLIs among all electrodes and between interest electrodes (C3, C4, P3, P4, T3, and T4) and other electrodes. Furthermore, we compared PLIs between CECTS and control data and analyzed the associations between PLIs and total seizure times in CECTS patients. Results: No differences were detected in clinical profiles or visual electroencephalography examinations between patients with CECTS and control participants. In patients with CECTS, the mean PLIs among all electrodes and toward interest electrodes were higher at the theta and alpha bands and lower at the delta and gamma bands than those in control participants. Additionally, the mean PLIs toward interest electrodes in the beta frequency band were negatively associated with seizure times (P = 0.02). Conclusion: The resting-state delta, theta, alpha, and gamma band PLIs might reflect an aberrant brain network in patients with CECTS. The resting-state PLI among the selected electrodes of interest in the beta frequency band may be a predictive marker of seizure times in patients with CECTS.

Failure to paint the left quarter of a watercolor and no error in a line drawing: a case report of an art teacher with unilateral spatial neglect.

A 54-year-old art teacher, experienced a right putaminal hemorrhage, and thereafter suffered severe left hemiplegia and unilateral spatial neglect, and was transferred to the rehabilitation department of the University Hospital 1 month after the onset. Although the unilateral spatial neglect was improving, the patient was unable to paint the left quarter of a watercolor, but there was no error in line drawing. The occurrence of errors only in a watercolor suggests that the neural process for painting a watercolor is different from that of line drawing.

Clinical course of a Japanese patient with developmental delay linked to a small 6q16.1 deletion.

There is only one report of patients with developmental delay due to a 6q16.1 deletion that does not contain the SIM1 gene. A 3-year-old female showed strabismus, cleft soft palate, hypotonia at birth, and global developmental delay. Exome sequencing detected a de novo 6q16.1 deletion (chr6: 99282717-100062596) (hg19). The following genes were included in this region: POU3F2, FBXL4, FAXC, COQ3, PNISR, USP45, TSTD3, CCNC, and PRDM13.

Gait disturbance in a patient with de novo 1.0-kb SOX2 microdeletion.

BACKGROUND: Sex-determining region Y-box 2 (SOX2) plays an important role in the early embryogenesis of the eye, forebrain, and hypothalamic-pituitary axis. Anophthalmia, microphthalmia, and hormonal abnormalities are commonly observed in patients with SOX2-related disorders. Although gait disturbance, particularly ataxic gait, has recently been observed in several cases, detailed data regarding the clinical course of gait disturbance in SOX2-related disorders are limited. CASE REPORT: A 9-year-old Japanese boy presented with focal dyskinesia only during walking and running after he started walking at the age of 3 years. He also exhibited intellectual disability and mild dysmorphic features, including microcephaly, micropenis, and short stature associated with hormonal abnormalities. Gait disturbance with involuntary extremity movements only during walking and running was indicative of choreoathetosis and dystonia. Genetic analysis detected a de novo heterozygous 1.0-kb deletion including SOX2 at 3q26.32, as described in a previous technical paper. CONCLUSIONS: SOX2-related disorders should be considered in patients with some anomalies having a differential diagnosis of dyskinesia. Focal dyskinesia only during walking and running may be a characteristic feature of SOX2-related disorders.

A case of ALG11-congenital disorders of glycosylation diagnosed by post-mortem whole exome sequencing.

INTRODUCTION: Congenital disorders of glycosylation (CDG) are inherited inborn errors of metabolism due to abnormal protein and lipid glycosylation that present with multi-systemic manifestations. The heterogeneity of CDG poses a serious diagnostic challenge; therefore, whole-exome sequencing (WES), which plays an increasingly important role in the molecular diagnosis of CDG, is used for examining patients with CDG. CASE REPORT: We report the case of a two-month-old male patient who developed developmental and epileptic encephalopathy (DEE) with intractable seizures and microcephaly. EEG demonstrated a suppression-burst (S-B) pattern, and MRI showed delayed myelination and progressive atrophic changes. Although CDG was clinically suspected, serum transferrin isoelectric focusing analysis appeared to be normal. The patient died by six years of age. Postmortem WES performed approximately 20 years after the patient's death revealed homozygous variants in ALG11 (NM_001004127.3: c.935A > C, p.Glu312Ala), and the patient was diagnosed with ALG11-CDG. CONCLUSION: We present a case of the patient with ALG11-CDG diagnosed using post-mortem WES. The EEG revealed a S-B pattern that indicated severely drug-resistant DEE, which was associated with poor prognosis. If a CDG is suspected, WES should be considered.

Impaired neuronal integrity in traumatic brain injury detected by 123I-iomazenil single photon emission computed tomography and MRI.

This study was aiming at investigating the extent of neuronal damage in cases of traumatic brain injury (TBI) with diffuse axonal injury (DAI) using 123I-iomazenil(IMZ) SPECT and MRI. We compared the findings in 31 patients with TBI without any major focal brain lesions and 25 age-matched normal controls. Subjects underwent 123I-IMZ SPECT and MRI, and also assessment by cognitive function tests. The partial volume effect of 123I-IMZ SPECT was corrected using MRI. In the patients with TBI, decreased spatial concentration of 123I-IMZ binding was detected in the medial frontal/orbitofrontal cortex, posterior cingulate gyrus, cuneus, precuneus, and superior region of the cerebellum. ROC analysis of 123I-IMZ SPECT for the detection of neuronal injury showed a high diagnostic ability of 123I-IMZ binding density for TBI in these areas. The decreased 123I-IMZ uptake density in the cuneus and precuneus was associated with cognitive decline after the injury. In the patients with TBI, brain atrophy was detected in the frontal lobe, anterior temporal and parietal cortex, corpus callosum, and posterior part of the cerebellum. Evaluation of the neuronal integrity by 123I-IMZ SPECT and MRI provides important information for the diagnosis and pathological interpretation in cases of TBI with DAI.

Clinical Characteristics of Fragile X Syndrome Patients in Japan.

BACKGROUND: Fragile X syndrome (FXS) is a well-known X-linked disorder clinically characterized by intellectual disability and autistic features. However, diagnosed Japanese FXS cases have been fewer than expected, and clinical features of Japanese FXS patients remain unknown. METHODS: We evaluated the clinical features of Japanese FXS patients using the results of a questionnaire-based survey. RESULTS: We presented the characteristics of seven patients aged 6 to 20 years. Long face and large ears were observed in five of seven patients. Macrocephaly was observed in four of five patients. The meaningful word was first seen at a certain time point between 18 and 72 months (median = 60 months). Developmental quotient or intellectual quotient ranged between 20 and 48 (median = 29). Behavioral disorders were seen in all patients (autistic spectrum disorder in six patients, hyperactivity in five patients). Five patients were diagnosed by polymerase chain reaction analysis, and two patients were diagnosed by the cytogenetic study. All physicians ordered FXS genetic testing for suspicious cases because of clinical manifestations. CONCLUSION: In the present study, a long face, large ears, macrocephaly, autistic spectrum disorder, and hyperactivity were observed in almost cases, and these characteristics might be common features in Japanese FXS patients. Our finding indicated the importance of clinical manifestations to diagnosis FXS. However, the sample size of the present study is small, and these features are also seen to patients with other disorders. We consider that genetic testing for FXS should be performed on a wider range of intellectually disabled cases.

Progressive cerebral atrophies in three children with COL4A1 mutations.

BACKGROUND: The collagen type IV alpha 1 chain (COL4A1) gene on 13q34 encodes one chain of collagen. COL4A1 mutations have been identified as the cause of a group of multisystemic conditions in humans, including the brain, eyes, kidneys, muscles, and other organs at any age. Brain imaging shows a wide spectrum of abnormalities, including porencephaly, schizencephaly, polymicrogyria focal cortical dysplasia, periventricular leukoencephalopathy, ventricular dysmorphisms, and multiple brain calcifications. However, there are no reports in the literature showing progressive radiological findings in consecutive follow-up scans. Herein, we report three cases of COL4A1 mutations with porencephaly from gestation to five years of age or longer, and describe their clinical and brain imaging findings. CASE REPORTS: We retrospectively reviewed the clinical symptoms and radiological findings, including brain magnetic resonance imaging (MRI) and computed tomography (CT), in three female patients with COL4A1 mutations. Their mutations were c.4843G>A (p.Glu1615Lys), c.1835G>A (p.Gly612Asp), and c.3556+1G>T respectively. All the three cases represented porencephaly in the fetal period; severe hemolytic anemia in the neonatal period; and drug-resistant epilepsy, global developmental delay, and spastic quadriplegia in their childhood. RESULTS: Brain MRI and CT showed progressive white matter atrophy from gestation to five-year follow-up or later. Minor cerebral hemorrhage without symptoms occasionally occurred in one patient. Despite brain changes, the clinical picture was stable during early childhood. CONCLUSIONS: COL4A1 mutations may cause progressive cerebral atrophy beyond early childhood.